1. Technical Field
The present invention relates generally to digital computers; and more particularly to a mouse used to position a cursor on the display of a digital computer.
2. Related Art
Digital computers have been known in the art for years. Personal digital computers typically include a case, a video display, and one or more input/output devices. The case typically includes a power supply, a cooling fan, a motherboard, interface ports, peripheral cards, a disk drive, and other components. Contained on the motherboard are a processor, memory, a processor chip set, and one or more peripheral buses. The peripheral cards interface input/output devices with the motherboard via the peripheral buses. Other input/output devices may couple directly to the motherboard via appropriate connectors, e.g., devices coupled via a parallel port, devices coupled via a serial port, and devices coupled via a USB.
Generally speaking, input/output devices receive input from a user or another source and/or provide output to a user or anther source. Keyboards and computer mice are typically considered input devices because they receive input from a user but provide no output to the user. Typical monitors are considered output devices because they provide output to the user but receive no input from the user. Touch sensitive monitors however, do receive input from a user and are also considered an input device. Audio speakers are output devices while audio microphones are input devices.
A great difficulty in the design and operation of personal computers relates to user interfaces. Such is the case because the interaction of humans with computers is a primary purpose of computers. The keyboard has been the primary user input device since the advent of personal computers. The computer mouse has become a popular input device due to its ease of use. The mouse allows a user to position a cursor on the display by altering the physical position of the mouse. Typically, the mouse resides on a horizontal surface, such as a mouse pad resting on a desktop, and contacts the horizontal surface. A tracking ball contacts the mouse pad and, when the position of the mouse is altered, the tracking ball changes its orientation with respect to the mouse. Electronics contained in the mouse sense the change in orientation of the tracking ball within the mouse and translate this into electronic signals. These electronic signals are transmitted to the motherboard via an interface, processed by software executing on the computer and result in a change in position of the cursor on the display.
Additional input devices on the mouse, such as push buttons, allow for additional operations, such as item selection, text highlighting, and dragging/dropping, for example. A mouse wheel may also be included that allows a user to scroll the computer""s display. With some mice, push buttons may be programmed to execute other functions as well, such as double click operations with a single button push.
Mice are designed to accommodate the range of motion of a user""s arm and/or wrist. The user""s arm and/or wrist provide a relatively large range of motion. To provide full screen cursor control, mice are designed so that a reasonable range of motion of the mouse provides full-screen cursor movement. However, this design makes fine cursor movement difficult. While fine cursor positioning is available by programming the mouse to have a lesser range of operation, the benefit of full screen cursor movement is defeated with these settings. Further, most users cannot provide fine levels of input with their arm/or wrist. Thus, it is difficult for most users to control the fine motion of a cursor using a mouse.
Thus, there is a need in the art for a mouse that provides full-screen cursor movement but at the same time allows for fine positioning of the cursor.
Thus, to overcome the shortcomings of the prior systems, among other shortcomings, a mouse constructed according to the present invention provides multiple cursor control input devices. A first input device is the traditional tracking ball input that operates when the position of the mouse is altered with respect to a surface upon which it resides. A second input device resides upon a surface of the mouse that is accessible with one or more of the user""s fingers. This second input device may be a tracking ball, a finger pad, or a joy stick, among other input devices. This second input device provides a secondary control of cursor movement that is combined with the input of the first input device to provide full cursor control.
In a described operation, the first input device provides coarse cursor control while the second input device provides fine cursor control. This configuration compliments the motor control available with a user""s hand and fingers. The user""s hand/wrist has coarser motor control than does the user""s fingers. Thus, the first input device is operated by motion of the user""s hand or wrist and provides coarse positioning of the cursor. Further, the second input device is operated by one or more fingers of the user and provides fine cursor positioning. Thus, while the first input device corresponds to the coarse motor control of the user""s hand/wrist in positioning the cursor, the second input device corresponds to the fine motor control of the user""s fingers in finely positioning the cursor.
In another embodiment of the present invention, the user provides input only via the first input device. However, a button on the mouse (or other toggling mechanism) adjusts the gain or scaling of the first input device between a coarser positioning and a finer positioning. In this fashion, the user may coarsely position the cursor on the display using the coarser setting, adjust the scaling of the input device, and finely position the cursor on the display using the finer setting.
Moreover, other aspects of the present invention will become apparent with further reference to the drawings and specification, which follow.